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Re: moly or mildsteel cage?
[Re: Monte_Smith]
#169654
12/19/08 03:51 PM
12/19/08 03:51 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
I don't push customers one way or the other either....but...as I stated, I TIG everything, MS or Moly. Here in this area, DOM is NOT that much cheaper than Moly, so, if you are only looking at a couple hundred dollars more for a Moly vs MS, what would you do Bob. You also have to consider my customer base. I do very little bracket type stuff and 25.5 is about the least spec we ever build. I also still maintain that Moly cars are worth more at resale and more desirable to potential buyers.
Monte
I'am not dis-agreeing with you Monte.I'am just stating facts from my perspective.The majority of our work is bracket cars.You deal with a limited market like you stated,25.5 spec and up.I try to relate to the majority of people on the site.I think you agree that most adverage racers here,including me are not in your league.My comments and advice is for us regular kinda of racers.Sorry if you think I was stepping on your toes.I not worthy of that. 
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Re: moly or mildsteel cage?
[Re: B G Racing]
#169655
12/19/08 08:16 PM
12/19/08 08:16 PM
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Joined: Jan 2003
Posts: 1,361
Wild West
M_D
pro stock
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pro stock
Joined: Jan 2003
Posts: 1,361
Wild West
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The cage design in the above photo examples were different, and chances are the mild steel cars were heavier too. Also, even though they all went on their tops, it's hard to say exactly where and how much the forces actually were. So I don't think the photos prove much of anything regarding MS versus CM. Having said that, I have nothing agaist CM, in fact I am of about the same mind as Monte and personally TIG everything and use only CM for reasons he stated.
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Re: moly or mildsteel cage?
[Re: Monte_Smith]
#169659
12/20/08 11:51 AM
12/20/08 11:51 AM
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Joined: Jan 2005
Posts: 3,699
Newport, Mi
Evil Spirit
master
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master
Joined: Jan 2005
Posts: 3,699
Newport, Mi
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Quote:
I don't push customers one way or the other either....but...as I stated, I TIG everything, MS or Moly.
Monte
Im curious as to why M/S cages are TIG'ed. The test of a weld is that when you try to pull it apart, the material around it fails before the weld. Since a MIG weld has a larger radius than a TIG you end up with a larger surface area and (theoretically) a stronger weld. Is it for looks? A good TIG weld is usually nicer looking, but it is usually easier to get a MIG gun into the cramped areas, and you don't have to deal with trying to operate the pedal with your knee, etc. Keep in mind, I am asking this as an honest question; I know that you are a very competent builder and am not trying to insult you.
Free advice and worth every penny...
Factory trained Slinky rewinder.........
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Re: moly or mildsteel cage?
[Re: Evil Spirit]
#169661
12/20/08 12:40 PM
12/20/08 12:40 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
Quote:
I don't push customers one way or the other either....but...as I stated, I TIG everything, MS or Moly.
Monte
Im curious as to why M/S cages are TIG'ed. The test of a weld is that when you try to pull it apart, the material around it fails before the weld. Since a MIG weld has a larger radius than a TIG you end up with a larger surface area and (theoretically) a stronger weld. Is it for looks? A good TIG weld is usually nicer looking, but it is usually easier to get a MIG gun into the cramped areas, and you don't have to deal with trying to operate the pedal with your knee, etc. Keep in mind, I am asking this as an honest question; I know that you are a very competent builder and am not trying to insult you.
A few of us here at BGR can make just as nice a weld with a mig as they can with a tig.It's just a little bigger weld.MS cages are usually .135 thick so when you weld two pieces of .135 material you want at least .270+- of weld width and at least the same weld thickness of the the material .135+- at the crown.These specs are from the Steamfitters weld testing for power plants and pressure vessels.  But then what in hell do I know,I was only certified in only 5 states for bridge and structural and heavy equipment modification and repair.I was a student of the late Art Livinston one of the best in the business.I didn't take the test for nucular power plants. 
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Re: moly or mildsteel cage?
[Re: B G Racing]
#169663
12/20/08 01:10 PM
12/20/08 01:10 PM
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Joined: Dec 2003
Posts: 22,695
Bitopia
jcc
If you can't dazzle em with diamonds..
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If you can't dazzle em with diamonds..
Joined: Dec 2003
Posts: 22,695
Bitopia
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Quote:
Quote:
Quote:
I don't push customers one way or the other either....but...as I stated, I TIG everything, MS or Moly.
Monte
Im curious as to why M/S cages are TIG'ed. The test of a weld is that when you try to pull it apart, the material around it fails before the weld. Since a MIG weld has a larger radius than a TIG you end up with a larger surface area and (theoretically) a stronger weld. Is it for looks? A good TIG weld is usually nicer looking, but it is usually easier to get a MIG gun into the cramped areas, and you don't have to deal with trying to operate the pedal with your knee, etc. Keep in mind, I am asking this as an honest question; I know that you are a very competent builder and am not trying to insult you.
A few of us here at BGR can make just as nice a weld with a mig as they can with a tig.It's just a little bigger weld.MS cages are usually .135 thick so when you weld two pieces of .135 material you want at least .270+- of weld width and at least the same weld thickness of the the material .135+- at the crown.These specs are from the Steamfitters weld testing for power plants and pressure vessels. But then what in hell do I know,I was only certified in only 5 states for bridge and structural and heavy equipment modification and repair.I was a student of the late Art Livinston one of the best in the business.I didn't take the test for nucular power plants.
Nice resume, but IMO you didn't answer his question. 
Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.
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Re: moly or mildsteel cage?
[Re: Evil Spirit]
#169665
12/20/08 01:51 PM
12/20/08 01:51 PM
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Joined: Nov 2004
Posts: 6,890
North Alabama
Monte_Smith
master
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master
Joined: Nov 2004
Posts: 6,890
North Alabama
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Quote:
The question wasn't directed at BGR - it was initially asked of Monty - he stated that he TIGs all cages, and I was politely asking why the preference of TIG over MIG. If it's for appearance, OK. If it's structural, how? 
I would rather TIG a cage, mostly because of appearance. I don't care how good you are with wire, a TIG weld looks better than a MIG by far. The weld is small and clean, plus there is no splatter. TIG welding also requires very precise fits, which again, makes the weld and the overall cage look better. As I stated, if I do use MS, it is DOM .120 wall. I never use that thick .134 wall stuff, as it is heavy, plus the spec is .120, so why use thicker. DOM will pass every time.....I never said everybody needed a MOLY cage...all I said was that since I TIG everything anyway and Moly is barely higher than DOM, it made no sense for ME to use MS, even on a simple cage. If you are thinking it would cost more for me to put a cage in your car, than a lot of other people, you would be right. I never claim to be the cheapest at anything, nor do I wish to be. I am a one man show and high quality is very important to me. If someone does not want to pay the extra for me to do something, I fully understand and have no hard feelings if they take it somewhere else. That has never been a problem though, as my backlog of work is pretty large.
Monte
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Re: moly or mildsteel cage?
[Re: Monte_Smith]
#169666
12/20/08 03:23 PM
12/20/08 03:23 PM
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Joined: Jan 2005
Posts: 3,699
Newport, Mi
Evil Spirit
master
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master
Joined: Jan 2005
Posts: 3,699
Newport, Mi
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Yeah, Monty, TIGed cages usually do look better, due to the better fit necessary and the quality of the welds. I was just curious as to your earlier post. I probably get involved with about 1-2 cages a year; I'll fit and tack them together and have someone more "ergonomically friendly" (100 lbs smaller) weld them in. We TIG C/M and MIG M/S - if they want a M/S TIGed, I tell them why I don't like to, and let them deal directly with my welder, or theirs after I do the basic fit and tack weld.
Free advice and worth every penny...
Factory trained Slinky rewinder.........
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Re: moly or mildsteel cage?
[Re: LA360]
#169667
12/20/08 05:08 PM
12/20/08 05:08 PM
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Joined: Jul 2005
Posts: 2,634
Right Coast
Fabman
master
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master
Joined: Jul 2005
Posts: 2,634
Right Coast
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Quote:
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Looking at that cage, a gusset to the windscreen bar and Door bar could have minimised that. It certainly does look worrying though. I can also see why certain builders use a straight bar from the door bar footing to where the windscreen bar joins the door bar.
AL....
Alan
Anyway you can post a pic of the gusset you are speaking about for this fix?
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Re: moly or mildsteel cage?
[Re: jcc]
#169669
12/20/08 08:31 PM
12/20/08 08:31 PM
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Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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Quote:
Quote:
Quote:
Quote:
I don't push customers one way or the other either....but...as I stated, I TIG everything, MS or Moly.
Monte
Im curious as to why M/S cages are TIG'ed. The test of a weld is that when you try to pull it apart, the material around it fails before the weld. Since a MIG weld has a larger radius than a TIG you end up with a larger surface area and (theoretically) a stronger weld. Is it for looks? A good TIG weld is usually nicer looking, but it is usually easier to get a MIG gun into the cramped areas, and you don't have to deal with trying to operate the pedal with your knee,
Nice resume, but IMO you didn't answer his question.
Thanks for the compliment on the resume.For that tight cage work set you TIG up with a small torch head and a thumb control.We hardly ever have to remove headliners on cars with full interior.Foot pedals are ok for bench work. 
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Re: moly or mildsteel cage?
[Re: B G Racing]
#169670
12/21/08 02:48 AM
12/21/08 02:48 AM
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Joined: Jan 2005
Posts: 3,699
Newport, Mi
Evil Spirit
master
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master
Joined: Jan 2005
Posts: 3,699
Newport, Mi
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Just kidding about the facts and logic, Bob. And like I said, I don't fit into the car to do the welding so I leave it up to the welder to do his thing; I think he finally bought the small torch that you mentioned. A few years ago I did a Mustang for a friend, and I hole-sawed holes under the floor plates. We fit the floor plates, loop, back bars, halo, and front down bars, then slid the floor plates out to drop the cage to weld. After the cage was welded we slid the floor plates back in, welded the tubes and floor, and braced the bottom of the floor to the rocker boxes. Came out really sweet. It wasn't as much work as it might sound, and it really got the halo tucked up into the roof.
Free advice and worth every penny...
Factory trained Slinky rewinder.........
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And most good design practices try to avoid "bending" in the first place, striving for just simple tension and compression forces thru triangulation, which negates much of the wall thickness advantages mentioned before. And most of these discussions usually result in those who are striving for crash protection, and the other camp striving for the most efficient and stiffess design, with the least material and lightest solution. Never ends.
We all know how that ends up.